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This paper presents an integrated control system for Sparse Matrix Converter (SMC) to interface Permanent Magnet Synchronous Generator (PMSG) based wind turbine unit with the power grid. A carrier based PWM technique is extended and adapted for the SMC. Details of the proposed switching strategy and derivations of the modulation functions for both the rectifier and inverter stages of the SMC are presented. The inverter stage is controlled to regulate the speed of the PMSG for maximum power extraction. In addition, the rectifier stage of the SMC is controlled to deliver the generated active power from the PMSG to the grid at the required power factor to satisfy the reactive power demand. Moreover, the proposed interface system is adaptively synchronized with the grid. The Multi-Output Recursive Least Square (MO-RLS) algorithm is proposed to estimate the phase angle of the grid voltage. Furthermore, active damping scheme is integrated with the proposed control system to attenuate the oscillations caused by the LC filter of the rectifier stage. Numerical simulations are conducted to investigate the effectiveness and the fast dynamic performance of the proposed control system based on MO-RLS even during the speed disturbance. The proposed interface system succeeds to control active power with the desired power factor demand and to damp the oscillations of the SMC current and voltage. [ABSTRACT FROM AUTHOR]

One of the attractive direct-drive wave energy conversion systems is the Archimedes Wave Swing (AWS) coupled to a Linear Permanent Magnet Synchronous Generator (LPMSG). This paper presents an integrated control strategy for the back-to-back converter interfacing the LPMSG not only to extract the maximum power from the wave, but also to ride-through the fault. The proposed maximum power tracking technique is based on speed sensorless control of the LPMSG. The unscented Kalman filter is adapted to estimate the translator velocity. The optimal velocity is obtained from the instantaneous active power at the generator terminals. Moreover, a low-voltage ride-through control is integrated to satisfy the grid-code requirements by injecting reactive current during grid disturbances. The generated active power at the fault instant is considered in determining the dynamic reactive power injection to not exceed the ratings of the grid-side converter. The superiority of the proposed strategy is the result of its ability to regulate the translator velocity that generates optimum power. Numerical simulations are conducted to evaluate the dynamic performance of the proposed integrated optimal strategy. Besides, it has been shown that the proposed methodology outdoes others by the decreased power fluctuations which leads to a reduction of the converter size. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a digital signal processor (DSP) based real time voltage envelope tracking system is developed and examined. The ADAptive LINEar neuron (ADALINE) and the Recursive Least Square (RLS) algorithms are adopted for envelope tracking. The proposed ADALINE and RLS algorithms give accurate results even under rapid dynamic changes. The paper investigates the effects of different parameters on the performance of the ADALINE algorithm and that of the RLS algorithm. The experimental system is cantered around a Texas Instrument 16bit fixed-point arithmetic (TMS320LF2407A) evaluation board. Both the ADALINE and the RLS tracking algorithms are developed using the DSP-assembly language. A simple voltage flicker generator is implemented to produce various voltage disturbances. Extensive tests of the proposed envelope tracking algorithms are conducted to evaluate their dynamic performance. [Copyright &y& Elsevier]

This paper presents a new induction motor speed estimation technique, which can estimate the rotor resistance as well, from the measured voltage and current signals. Moreover, the paper utilizes a novel adaptive linear combiner (ADALINE) structure for speed and rotor resistance estimations. This structure can deal with the multi-output systems and it is called MO-ADALINE. The model of the induction motor is arranged in a linear form, in the stationary reference frame, to cope with the proposed speed estimator. There are many advantages of the proposed unit such as wide speed range capability, immunity against harmonics of measured waveforms, and precise estimation of the speed and the rotor resistance at different dynamic changes. Different types of induction motor drive systems are used to evaluate the dynamic performance and to examine the accuracy of the proposed unit for speed and rotor resistance estimation. [Copyright &y& Elsevier]

• A finite-state-machine (FSM) based controller for microgrid converters is presented. • Performance recovery controller accounts for uncertainties and parameters variations. • The dynamic performance of DC microgrids based on FSM controller is limited. • Results showed fast response and resiliency of the performance recovery controller. • Unlike PI, performance recovery controller successfully manages disturbances. Droop technique is extensively adopted in dc microgrids, for both islanded and grid-connected modes of operation. However, voltage regulation and proper current sharing are considered as the major challenges in droop techniques. Moreover, changes in system parameters and wide load demand variations degrade the operational performance and the efficiency of the dc microgrid. In this paper, a finite-state-machine (FSM) based controller for the inner loop of microgrid converters is utilized. Although the FSM controller operates in voltage mode and requires no current sensors, the dynamic performance of the microgrid converters is limited. Thus, a distributed consensus output voltage tracking based on the performance recovery controller is presented which adopts nonlinear observers for the microgrid converters to account for model uncertainties and disturbances due to parameters variations. The dynamic performance and robustness of the FSM controller and performance recovery controller are assessed using PSCAD/EMTDC simulation. Moreover, a comparative study with the classical Proportional-Integral (PI) controller is presented, considering both rating-based and cost-based current sharing schemes of the dc microgrids. [ABSTRACT FROM AUTHOR]